Here's an interesting "What If" that was inspired by Saburo Sakai.
He stated that if the Germans had A6M2's during the Battle of Britain, the outcome might have been different.
The A6M saw it operational debut in September, 1940. Certainly in the right timeframe.
It had the range to rove all over the UK, and was certainly more maneuverable than the Spitfire or Hurricane, as was proven when the RAF fielded both aircraft in the early days of the Pacific.
British pilots early on didn't appreciate the Zero's performance, and got their heads handed to them until they paid heed to the guys that had been flying P-40's, and NOT dogfighting the Japanese. Based on an RAF squadron that had fought the Germans, and expected the Zero to be meat on the table. The table turned in a big way.
So think in terms of 1940. The Germans have a fighter that had the range to attack the RAF anywhere in the UK, stay with the bombers, pretty much the same firepower as the Me-109, not as fast or a high ceiling as the Spitfire.
How long would it take the RAF to figure out the hit and run tactics to fight the Zero, before they were decimated. They were already teetering by September 1940.